Method of uniting dissimilar metals



enoRGE A. MEAD, or MANsrrnL-o, onto, rc rire c anlass Germani', or

` Appiicatia y 4My invention relates to the method ot electrically-` connecting or bonding track rails used in electric haulage systems.

My invention has in View a `method of connecting the adjacent rails so as to form a continuous conductor by electrically u'feldinJ or hiazing the terminals of a bond to a suf--Y face 4of the rail. There are Various ways et applying loondsV to -rails throughl the medi um of the `electric current but the method of applying the electric current and the method, which I employ is that of heating the various .parts by passing the current through the assembled parts until the infusion of the parts to he united takes place, cr by applying an element to the bond terminal which .is brought up to a high heat hy an electric current.

This method 'of applying the elect "c ou'r1 rent inuniting a rail bond to a rail is ci. but my inventionresides more particularly in the application of the electric current in this way in combination with and arrangement ofvarious parts vand various steps as herein more fully described and claimed.

The description of the drawings and in. vention isv as follows:

Figure 1 shows a face elevation View of the hond which I propose to use.A

Fig. 2 shows a top plan view ofthe hond. Fig. 3 shows an end elevation' View of the hond.

Fig. 4c shows a section of a terminal of 'the bond on the line lf-4l of Fig. l.

Fig. 5 lshows a modified section. of 'the hond, terminal.

- c Fig. fishows another m'odiication in secv.tion of the bond terminal.

` arrangement N method of application ofi the bond'together 7 shows a sideel'evation'View ofthe Fig.

of the parts showing the with an indication of theinethod of. apply- .ing the electric current to. the parts.

Fig.` 9 showsa modification of' Fig. 8 and Speel-mation ci Eats-nt.

filed 'anuaiiy I' and as shown in Fig. 5 in i'vhich the prot( ja'tented tay 25, lt).

Serial. lilo. 356,101.

.t method applying the electric plying houdsto rails hy current 'which ispassed fd und rail for; the purpose througl of hafrting the cont-,i

or without an n posed metal actingr brace," and where a carbon blocl; p to'tlieouteiface o'ftliet rminal for thhepu'.- pose of the hond up to a gice et through 4Hhe part I that the Contactin f ith the carboi:

right up to a melting teine contacting faces between hond c Y and tlierail and in some i the jij inal is actually melted down en irely. .Edy invention has in 'View 'the overcoming this diiculty and resides in. inwi'posing between the carbonI block and 'very apt peratur;

'the copperterniinal of the rail bond as here-- toiture used i plateci' metal having a higher inciting ,pt than the coijipei of the terminal. T .is interposed' high melting .point metal can he ei ier separable 'from the bond or securely attached to the saine to i'oiin a fc3. 1 cond and this latter consiruction the resistance between show hond in which nu esente the body ci a hond of a y arnet-er and 2 represents the terminals s eciued to the 1cody l. The 'terminels are coi posed of two parts, namely the coppe "s which "aces the rail indicated by 3 L otectiug plate i which. is secured to t"- e terminal part y direct weldn ing or hrazi The protecting pl may he compose iron, steel, nickel i h i metal having a higher meltn ing poin than the part'. 1

The protecting plate l is shown as being applied to one face of the terminal, namely cli th W ci c the tace which is applied to the i hut his `protecting plate can afso l d to all faces of the bond terminal oe ext excepting that which is applied to the rail cting faces, either with vuntil the parts have vthereby unitin g depending In Fig. 6 the modiiication shown com prises a terminal in which the conducting portion is composed oi' individual layers ot conducting material, preferably copper, and indicated by the numeral 6 and having protecting plate 7 inclosinp; three thereof. The protecting plate l is preterably united to the individual layers 6 along its face which isopposite to the face oi terminal which is applied to the ii In Figs. 7 and 8 are shown the method and relation of the various parts in making an application of my invention and in these figures l have shown a' rail t3 provided with a {ish-plate 9 as is usual at the end let rails and a bond engaging the face ot the rail and held thereto by a carbon block l0. interposed between the copper terminal and the face of the rail 8 is shown a strip oi brazing metal l1 and interposed between the copper terminal 3 and the carbon block l0 is shown a plate of metal Ll'liaving a higher melting pointfthan the copper terminal Suilicient pressure by suitable apparatus is applied to the block 10 to hold all parts in close conY tact and relative position on the rail.

The electric current used 'for heating the various parts may be secured 'from any suitable source and l have illustrated source consisting of a generator A ha fing one terF minal connected to the rail and the other terminal connected to the carbon bloch. The current iioiving through the rail and blo/cli and through the bond is controlled by a ariable resistance lt connected in series with -the field F and both of which are connected to the terminals of the generator.

After the parts have been arranged in position as shown in Figs. 7 and S the cur rent is caused to pass through the rail S, brazing metal 1l, copper ol the terminal il, the interposed metal plate Li; and the carbon block l0 and the current value is increased. become sufiiciently heated so that the brazing metal il is fused,

the bond and rail together. During the period of heating the mrbon block 10 T.Till be brought up to an incandescent heat which is 'far in excess et the melting point of the copper but when the block 1 0 is in contact with the copper 3 it istound that the terminal Bis very liable to be fused and many times entirely melted away hefore the heat in the rail has become sufficiently high or the bracing metal il fused and this diliiculty is overcome by interposing between the carbon block l0 and the copper of the terminal 3 the high melt-ing oint plate et.

The melting point or copper is approximately 19800 Fahrenheit and' that o iron approXiruatelyl 2785 to 28000 Fahrenheit, upon the grade.- he the interposed metal plate l is preferably Welded. to the copper o" the terminal 3, the contact reiel .liable union between face `ance between the parte 'and 4l Vwill be a minimum and il be very much i 'he Contact .resistance between block l0 and the part l? will ,3e found. by this method or' bondin can all be brought up to a 3 heat more uniformly when t er other high resistance ria lar charact contacts with the copper terminal 3 and the result. will. be a more rcthe rail and the bond in bonding as many through present methods by the terminal. being entirely melted away and having be replaced. Also the care required by the operator is less with my herein disclosed method than with 'other methods.

.ln Fig. 9 l show attachment ci the e carbon block al of a simi-- and great economy bonds e lost entirely a mediiication ot the lectric circuits and application olf, the heating current in that the current is p ssed through the electrode only which is brought up to the desired heat.

Having described my method what 'I claim is:

il. The nietliiod et unitiu metals oit vi". nlil e heat conductiv' f and di'liercnt temperatures of fusion coinphs'ing' the steps el holding the parts in contact at the desired point ot union by pressing an electrodo ci high re si ce egsinst the part having the lowest, melting point and greatest heat conductivity with a plate et metal interposed having a lower heat conductivity and higher melting point than the aforesaid metal, then passing an electric current through the elec trede and preducing` a high temperature therein 'which is transmitted" to the 'metal parts to be united by conduction, said heat to be applied until the metals to beaunited are brought to a 'temperatureat Awhich they will unite. l l

The method or unitinfc` tivo metals oft unlilre heat conductivity by applying heat trein an external source consisting in the steps oi? holding said metals in contact at the desired point of union and having interJ posed between the ext nal source ot heat one olf the metals to be united a metal plate having a higher meltingr point than that ci" the metal. having the higher heat conductivity, and then applying heat vtroni an external source to be transmitted to the part-s by conduction until the parts to be united are brought up to a Welding heat.

3. The method ot uniting a bond to a rail consisting oi the 'steps or' interposing between said bond :ind rail'at the desired point or union a relatively more fusible material, then holding the bodies in contact-with such material interposed, then 'pressing .an electrode of high resistance against lthe louter the bond with ai'fii'iterposed metal ot greater fusi -ity than the bond and then an electric current through the elecand uw y* man semina in f 

